Diterpenes and triterpenes show potential as biocides against pathogenic fungi and oomycetes: a screening study

Abstract

Objectives The aim was to screen di- and triterpenes as potential biocides against fungal pathogens (Alternaria sp., Fusarium avenaceum, F. sambucinum, Botrytis cinerea, Botryotina fuckeliana, Mycocentrospora acerina, Cylindrocarpon sp.) and oomycetes (Phytophthora cactorum, P. fragariae). Results We measured the antifungal activity of terpenes by estimating the growth area, ergosterol content and level of lipid peroxidation. Fungi and oomycetes were grown on solid media in Petri dishes. As a positive control, we used a common synthetic fungicide, fosetyl-Al. Di- and triterpenes showed promising potential as biocides against most of the studied species. The responses of fungi and oomycetes were dependent on the specific type of terpenes and identity of the fungi. Compared to synthetic fungicide, terpenes were equally effective as antifungal agents and even more effective for some species, especially for oomycetes. The terpene mode of action includes inhibition of ergosterol synthesis and increased lipid peroxidation. Conclusions Di- and triterpenes, natural compounds that are very abundant in northern countries, are excellent candidates for biocides.

Recent advances in the use of Trichoderma-containing multicomponent microbial inoculants for pathogen control and plant growth promotion

“…are crucial for their antifungal activities. Terpenes inhibit fungal growth (Adamczyk et al 2023 ) and pyrones interfere with spore germination and mycelial growth (Liu et al 2022a ; Degani and Gordan 2022 ). Others, such as gliotoxin and gliovirin, originally identified as antibiotic substances in some Trichoderma species, can induce oxidative stress and disrupt the intracellular redox homeostasis in fungal cells (Scharf et al 2016 ).…”